#include <stdio.h>
#include <math.h>
int main()
{
     float a,b,c,s,area;
     printf("please enter the a,b,c");
     scanf("%f,%f,%f",&a,&b,&c);
     s=(a+b+c)/2;
     if((a+b>c)&&(a+c>b)&&(b+c>a))
     {
     area=sqrt(s*(s-a)*(s-b)*(s-c));
     printf("The area is %f",area);
     }
     
     else
     {
         printf("It can not be a triangle.");

     }

return 0;
}